The group, alongside wildlife trade monitoring network TRAFFIC, say it could mean the haul is part of one of the biggest unregulated ivory markets in Asia.

They found 3,300 pieces of ivory and almost 50 raw ivory elephant tusks openly for sale in Mong La, a town which borders China – the sale of which is largely illegal in Myanmar.

According to its sources, ivory enters the town from China, mainly already carved.

The material, derived from tusks and teeth, was thought to have come from Africa.

Several shops were openly showing hundreds of carved pieces of ivory in glass display cases.

Professor Vincent Nijman, from Oxford Brookes University, said the team was made up of students studying primate conservation.

He said: “Our observations suggest Mong La may be one of the biggest unregulated ivory markets in Asia, and it is doubtless one of those where ivory is most openly displayed.”

Dr Chris R Shepherd, director of TRAFFIC in South-East Asia, said: “Increasing volumes of ivory in an open cross-border market catering to Chinese consumers is a sure sign that international agreements are not being enforced and action to reduce ivory demand is not effective.”